It is well-known that a watch comprises a body and a strap. The body is a main functional element in a watch, in which an electrical movement, a mechanical movement, or a quarter movement is installed. An outside surface of the body is provided with a display window to show time. The body is connected with the strap. Users may wear watches by wrapping the strap on their wrists, thus providing the user a convenience of carrying on the watch.
In the present time, a watch is more than a time tool. It has been much more often used as an ornament. Even in a world with rapidly developed high-technology, watches are still very popular for human beings. However, decorating elements in a traditional watch are usually directly attached onto the strap or the body, thus causing a deficiency that the decorating element may not be replaced. Such watches have very simple decorating functions, and are not competitive in the market.